MONTPELIER, Vt. — Gov. Peter Shumlin and the chairman of the Senate Judiciary Committee have announced legislation “to cautiously and deliberately” legalize recreational marijuana in Vermont.

Sen. Richard Sears, a Democrat, said Tuesday that the bill would remove the civil penalties for possession of an ounce or less of marijuana for those over 21 but also provide for enhanced penalties for people over 21 who furnish alcohol or marijuana to minors.

Shumlin, a Democrat, said the proposal meets criteria he outlined in his State of the State address, including strengthening law enforcement capacity to respond to drugged drivers and keeping marijuana out of the hands of children.

Revenue from a special tax would be used to help pay for drug addiction programs and to add more state troopers.

“The war on drugs has failed when it comes to marijuana prohibition,” Shumlin said in a statement on the governor’s website. “Under the status quo, marijuana use is widespread, Vermonters have little difficulty procuring it for personal use, and the shadows of prohibition make it nearly impossible to address key issues like prevention, keeping marijuana out of the hands of minors, and dealing with those driving under the influence who are already on Vermont’s roads. The system has failed.

“The question for us is how do we deal with that failure. Vermont can take a smarter approach that regulates marijuana in a thoughtful way, and this bill provides a framework for us to do that.”

Shumlin outlined five legalization principles in his State of the State Address. Via Shumlin’s online statement:

• A legal market must keep marijuana and other drugs out of the hands of underage kids. With 83 percent of Vermont youth saying that marijuana is easy or somewhat easy to obtain, the current system doesn’t do this.

• The tax imposed must be low enough to wipe out the black market and get rid of the illegal drug dealers.

• Revenue from legalization must be used to expand addiction prevention programs.

• Law enforcement’s capacity to improve the response to impaired drivers under the influence of marijuana who are already on Vermont’s roads must be strengthened.